I answer, it cannot; for it is then only a particular occurrence of the quality (if I may so use the word) of oneness. But, then, if we so understand the term, the argument loses all significance. We cannot call "a one" of this kind a container or a thing contained, or talk of it as encircled by anything. We do not even try to imagine it as moving on its centre, or passing from place to place, or coming into being in anything, or being at rest in anything. Such language we use only in speaking of things. It seems to me plain that the speaker is thinking of one as a thing, and it is this that gives its charm to the bundle of paradoxes. The Eleatic "one" was always a thing and not mere unity or an occurrence of unity. My criticism of the reasoning is, I think, just. And whether Plato is responsible for the Parmenides or not, we must agree that such a confusion of "the one" and "a one" (as an object) would not be foreign to his modes of thought. His world of Ideas is peopled with "the"'s turned into "a"'s, a fact which his acute pupil Aristotle was not slow to discover.[36]
SEC. 26. Aristotle has again and again discussed with his usual keenness the kinds of sameness. He saw well enough that the word is ambiguous, and may with equal right be employed in speaking of experiences which do or do not contain an element of duality. He has pointed out that the law of non-contradiction has to do with sameness of the first kind, and not with the others.[37] His question as to "Socrates" and "Socrates sitting," his treatment of "Coriscus" and "the musical Coriscus," his statement that the white and the musical are the same when they are accidents in the same subject,[38] show that he clearly understood the significance of sameness in sense third. He gives us sense fourth when he says that things may be called the same when they belong to the same species or genus.[39] In his polemic against the Protagorean doctrine of relativity,[40] senses sixth and seventh come to the surface, though they are not very clearly or exhaustively discussed. The fallacy in the apparent possibility of attributing contradictory predicates to the same subject, from the fact that the same wine may appear sweet to one taster and not sweet to another, or at one time sweet and at another not sweet to the one palate, is laid bare in the distinction between kinds of sameness. Aristotle distinguishes between the wine itself and the sensations it produces in different persons, and he recognizes the fact that one man's perception of the "same" wine need not be wholly like that of another. But this does not imply any violation of the law of non-contradiction, for each sensation is just what it is at any instant; and the statement that the same wine is sweet and not sweet at the one moment amounts only to saying that the one object can cause dissimilar sensations in two minds at one moment. As much may be said for the non-simultaneous sensations of the one man. Sensations differing in time are two, and may differ without violating any law. In marking the fact that when we say two men perceive the same thing we do not mean that the immediate object of knowledge is in the two cases strictly one, but merely that these two objects are related in a peculiar way, Aristotle draws the line between sameness in sense first and in sense sixth. As to sense seventh. He distinguishes between the apparent and the real, and yet goes on speaking, quite in modern fashion, as though one thing could serve for both. He points out, _à propos_ of pressing upon the eyeball and doubling the visual image, that there is a distinction between the apparent and the real, and then closes the paragraph with the remark that "to those persons who do not move their organ of vision that which is one appears one."[41] This language would certainly seem to indicate that that which is appears--or that they are the same in some strict sense of the word. The sentence reads much in the style of Mr. Spencer or Sir William Hamilton.